package io.selendroid.testapp.server;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.URLEncoder;
import java.util.Date;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Locale;
import java.util.Properties;
import java.util.StringTokenizer;
import java.util.TimeZone;
import java.util.Vector;

/**
 * A simple, tiny, nicely embeddable HTTP 1.0 (partially 1.1) server in Java
 * 
 * <p>
 * NanoHTTPD version 1.25, Copyright &copy; 2001,2005-2012 Jarno Elonen (elonen@iki.fi,
 * http://iki.fi/elonen/) and Copyright &copy; 2010 Konstantinos Togias (info@ktogias.gr,
 * http://ktogias.gr)
 * 
 * <p>
 * <b>Features + limitations: </b>
 * <ul>
 * 
 * <li>Only one Java file</li>
 * <li>Java 1.1 compatible</li>
 * <li>Released as open source, Modified BSD licence</li>
 * <li>No fixed config files, logging, authorization etc. (Implement yourself if you need them.)</li>
 * <li>Supports parameter parsing of GET and POST methods (+ rudimentary PUT support in 1.25)</li>
 * <li>Supports both dynamic content and file serving</li>
 * <li>Supports file upload (since version 1.2, 2010)</li>
 * <li>Supports partial content (streaming)</li>
 * <li>Supports ETags</li>
 * <li>Never caches anything</li>
 * <li>Doesn't limit bandwidth, request time or simultaneous connections</li>
 * <li>Default code serves files and shows all HTTP parameters and headers</li>
 * <li>File server supports directory listing, index.html and index.htm</li>
 * <li>File server supports partial content (streaming)</li>
 * <li>File server supports ETags</li>
 * <li>File server does the 301 redirection trick for directories without '/'</li>
 * <li>File server supports simple skipping for files (continue download)</li>
 * <li>File server serves also very long files without memory overhead</li>
 * <li>Contains a built-in list of most common mime types</li>
 * <li>All header names are converted lowercase so they don't vary between browsers/clients</li>
 * 
 * </ul>
 * 
 * <p>
 * <b>Ways to use: </b>
 * <ul>
 * 
 * <li>Run as a standalone app, serves files and shows requests</li>
 * <li>Subclass serve() and embed to your own program</li>
 * <li>Call serveFile() from serve() with your own base directory</li>
 * 
 * </ul>
 * 
 * See the end of the source file for distribution license (Modified BSD licence)
 */
public class NanoHTTPD {
  // ==================================================
  // API parts
  // ==================================================

  /**
   * Override this to customize the server.
   * <p>
   * 
   * (By default, this delegates to serveFile() and allows directory listing.)
   * 
   * @param uri Percent-decoded URI without parameters, for example "/index.cgi"
   * @param method "GET", "POST" etc.
   * @param parms Parsed, percent decoded parameters from URI and, in case of POST, data.
   * @param header Header entries, percent decoded
   * @return HTTP response, see class Response for details
   */
  public Response serve(String uri, String method, Properties header, Properties parms,
      Properties files) {
    myOut.println(method + " '" + uri + "' ");

    Enumeration e = header.propertyNames();
    while (e.hasMoreElements()) {
      String value = (String) e.nextElement();
      myOut.println("  HDR: '" + value + "' = '" + header.getProperty(value) + "'");
    }
    e = parms.propertyNames();
    while (e.hasMoreElements()) {
      String value = (String) e.nextElement();
      myOut.println("  PRM: '" + value + "' = '" + parms.getProperty(value) + "'");
    }
    e = files.propertyNames();
    while (e.hasMoreElements()) {
      String value = (String) e.nextElement();
      myOut.println("  UPLOADED: '" + value + "' = '" + files.getProperty(value) + "'");
    }

    return serveFile(uri, header, myRootDir, true);
  }

  /**
   * HTTP response. Return one of these from serve().
   */
  public class Response {
    /**
     * Default constructor: response = HTTP_OK, data = mime = 'null'
     */
    public Response() {
      this.status = HTTP_OK;
    }

    /**
     * Basic constructor.
     */
    public Response(String status, String mimeType, InputStream data) {
      this.status = status;
      this.mimeType = mimeType;
      this.data = data;
    }

    /**
     * Convenience method that makes an InputStream out of given text.
     */
    public Response(String status, String mimeType, String txt) {
      this.status = status;
      this.mimeType = mimeType;
      try {
        this.data = new ByteArrayInputStream(txt.getBytes("UTF-8"));
      } catch (java.io.UnsupportedEncodingException uee) {
        uee.printStackTrace();
      }
    }

    /**
     * Adds given line to the header.
     */
    public void addHeader(String name, String value) {
      header.put(name, value);
    }

    /**
     * HTTP status code after processing, e.g. "200 OK", HTTP_OK
     */
    public String status;

    /**
     * MIME type of content, e.g. "text/html"
     */
    public String mimeType;

    /**
     * Data of the response, may be null.
     */
    public InputStream data;

    /**
     * Headers for the HTTP response. Use addHeader() to add lines.
     */
    public Properties header = new Properties();
  }

  /**
   * Some HTTP response status codes
   */
  public static final String HTTP_OK = "200 OK", HTTP_PARTIALCONTENT = "206 Partial Content",
      HTTP_RANGE_NOT_SATISFIABLE = "416 Requested Range Not Satisfiable",
      HTTP_REDIRECT = "301 Moved Permanently", HTTP_NOTMODIFIED = "304 Not Modified",
      HTTP_FORBIDDEN = "403 Forbidden", HTTP_NOTFOUND = "404 Not Found",
      HTTP_BADREQUEST = "400 Bad Request", HTTP_INTERNALERROR = "500 Internal Server Error",
      HTTP_NOTIMPLEMENTED = "501 Not Implemented";

  /**
   * Common mime types for dynamic content
   */
  public static final String MIME_PLAINTEXT = "text/plain", MIME_HTML = "text/html",
      MIME_DEFAULT_BINARY = "application/octet-stream", MIME_XML = "text/xml";

  // ==================================================
  // Socket & server code
  // ==================================================

  /**
   * Starts a HTTP server to given port.
   * <p>
   */
  public NanoHTTPD(int port, File wwwroot) {
    try {
      myTcpPort = port;
      this.myRootDir = wwwroot;
      myServerSocket = new ServerSocket(myTcpPort);
      myThread = new Thread(new Runnable() {
        public void run() {
          try {
            while (true)
              new HTTPSession(myServerSocket.accept());
          } catch (IOException ioe) {}
        }
      });
      myThread.setDaemon(true);
      myThread.start();
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }

  /**
   * Stops the server.
   */
  public void stop() {
    try {
      myServerSocket.close();
      myThread.join();
    } catch (IOException ioe) {} catch (InterruptedException e) {}
  }

  /**
   * Handles one session, i.e. parses the HTTP request and returns the response.
   */
  private class HTTPSession implements Runnable {
    public HTTPSession(Socket s) {
      mySocket = s;
      Thread t = new Thread(this);
      t.setDaemon(true);
      t.start();
    }

    public void run() {
      try {
        InputStream is = mySocket.getInputStream();
        if (is == null) return;

        // Read the first 8192 bytes.
        // The full header should fit in here.
        // Apache's default header limit is 8KB.
        int bufsize = 8192;
        byte[] buf = new byte[bufsize];
        int rlen = is.read(buf, 0, bufsize);
        if (rlen <= 0) return;

        // Create a BufferedReader for parsing the header.
        ByteArrayInputStream hbis = new ByteArrayInputStream(buf, 0, rlen);
        BufferedReader hin = new BufferedReader(new InputStreamReader(hbis));
        Properties pre = new Properties();
        Properties parms = new Properties();
        Properties header = new Properties();
        Properties files = new Properties();

        // Decode the header into parms and header java properties
        decodeHeader(hin, pre, parms, header);
        String method = pre.getProperty("method");
        String uri = pre.getProperty("uri");

        long size = 0x7FFFFFFFFFFFFFFFl;
        String contentLength = header.getProperty("content-length");
        if (contentLength != null) {
          try {
            size = Integer.parseInt(contentLength);
          } catch (NumberFormatException ex) {}
        }

        // We are looking for the byte separating header from body.
        // It must be the last byte of the first two sequential new lines.
        int splitbyte = 0;
        boolean sbfound = false;
        while (splitbyte < rlen) {
          if (buf[splitbyte] == '\r' && buf[++splitbyte] == '\n' && buf[++splitbyte] == '\r'
              && buf[++splitbyte] == '\n') {
            sbfound = true;
            break;
          }
          splitbyte++;
        }
        splitbyte++;

        // Write the part of body already read to ByteArrayOutputStream f
        ByteArrayOutputStream f = new ByteArrayOutputStream();
        if (splitbyte < rlen) f.write(buf, splitbyte, rlen - splitbyte);

        // While Firefox sends on the first read all the data fitting
        // our buffer, Chrome and Opera sends only the headers even if
        // there is data for the body. So we do some magic here to find
        // out whether we have already consumed part of body, if we
        // have reached the end of the data to be sent or we should
        // expect the first byte of the body at the next read.
        if (splitbyte < rlen)
          size -= rlen - splitbyte + 1;
        else if (!sbfound || size == 0x7FFFFFFFFFFFFFFFl) size = 0;

        // Now read all the body and write it to f
        buf = new byte[512];
        while (rlen >= 0 && size > 0) {
          rlen = is.read(buf, 0, 512);
          size -= rlen;
          if (rlen > 0) f.write(buf, 0, rlen);
        }

        // Get the raw body as a byte []
        byte[] fbuf = f.toByteArray();

        // Create a BufferedReader for easily reading it as string.
        ByteArrayInputStream bin = new ByteArrayInputStream(fbuf);
        BufferedReader in = new BufferedReader(new InputStreamReader(bin, "UTF-8"));

        // If the method is POST, there may be parameters
        // in data section, too, read it:
        if (method.equalsIgnoreCase("POST")) {
          String contentType = "";
          String contentTypeHeader = header.getProperty("content-type");
          StringTokenizer st = new StringTokenizer(contentTypeHeader, "; ");
          if (st.hasMoreTokens()) {
            contentType = st.nextToken();
          }

          if (contentType.equalsIgnoreCase("multipart/form-data")) {
            // Handle multipart/form-data
            if (!st.hasMoreTokens())
              sendError(
                  HTTP_BADREQUEST,
                  "BAD REQUEST: Content type is multipart/form-data but boundary missing. Usage: GET /example/file.html");
            String boundaryExp = st.nextToken();
            st = new StringTokenizer(boundaryExp, "=");
            if (st.countTokens() != 2)
              sendError(
                  HTTP_BADREQUEST,
                  "BAD REQUEST: Content type is multipart/form-data but boundary syntax error. Usage: GET /example/file.html");
            st.nextToken();
            String boundary = st.nextToken();

            decodeMultipartData(boundary, fbuf, in, parms, files);
          } else if (contentType.toLowerCase().startsWith("application/json")) {
            StringBuffer sb = new StringBuffer();
            String line = null;
            while ((line = in.readLine()) != null) {
              sb.append(line + "\n");
            }
            parms.put("json", sb.toString());
          } else {
            // Handle application/x-www-form-urlencoded
            String postLine = "";
            char pbuf[] = new char[512];
            int read = in.read(pbuf);
            while (read >= 0 && !postLine.endsWith("\r\n")) {
              postLine += String.valueOf(pbuf, 0, read);
              read = in.read(pbuf);
            }
            postLine = postLine.trim();
            decodeParms(postLine, parms);
          }
        }

        if (method.equalsIgnoreCase("PUT")) files.put("content", saveTmpFile(fbuf, 0, f.size()));

        // Ok, now do the serve()
        Response r = serve(uri, method, header, parms, files);
        if (r == null)
          sendError(HTTP_INTERNALERROR, "SERVER INTERNAL ERROR: Serve() returned a null response.");
        else
          sendResponse(r.status, r.mimeType, r.header, r.data);

        in.close();
        is.close();
      } catch (IOException ioe) {
        try {
          sendError(HTTP_INTERNALERROR, "SERVER INTERNAL ERROR: IOException: " + ioe.getMessage());
        } catch (Throwable t) {}
      } catch (InterruptedException ie) {
        // Thrown by sendError, ignore and exit the thread.
      }
    }

    /**
     * Decodes the sent headers and loads the data into java Properties' key - value pairs
     **/
    private void decodeHeader(BufferedReader in, Properties pre, Properties parms, Properties header)
        throws InterruptedException {
      try {
        // Read the request line
        String inLine = in.readLine();
        if (inLine == null) return;
        StringTokenizer st = new StringTokenizer(inLine);
        if (!st.hasMoreTokens())
          sendError(HTTP_BADREQUEST, "BAD REQUEST: Syntax error. Usage: GET /example/file.html");

        String method = st.nextToken();
        pre.put("method", method);

        if (!st.hasMoreTokens())
          sendError(HTTP_BADREQUEST, "BAD REQUEST: Missing URI. Usage: GET /example/file.html");

        String uri = st.nextToken();

        // Decode parameters from the URI
        int qmi = uri.indexOf('?');
        if (qmi >= 0) {
          decodeParms(uri.substring(qmi + 1), parms);
          uri = decodePercent(uri.substring(0, qmi));
        } else
          uri = decodePercent(uri);

        // If there's another token, it's protocol version,
        // followed by HTTP headers. Ignore version but parse headers.
        // NOTE: this now forces header names lowercase since they are
        // case insensitive and vary by client.
        if (st.hasMoreTokens()) {
          String line = in.readLine();
          while (line != null && line.trim().length() > 0) {
            int p = line.indexOf(':');
            if (p >= 0)
              header.put(line.substring(0, p).trim().toLowerCase(), line.substring(p + 1).trim());
            line = in.readLine();
          }
        }

        pre.put("uri", uri);
      } catch (IOException ioe) {
        sendError(HTTP_INTERNALERROR, "SERVER INTERNAL ERROR: IOException: " + ioe.getMessage());
      }
    }

    /**
     * Decodes the Multipart Body data and put it into java Properties' key - value pairs.
     **/
    private void decodeMultipartData(String boundary, byte[] fbuf, BufferedReader in,
        Properties parms, Properties files) throws InterruptedException {
      try {
        int[] bpositions = getBoundaryPositions(fbuf, boundary.getBytes());
        int boundarycount = 1;
        String mpline = in.readLine();
        while (mpline != null) {
          if (mpline.indexOf(boundary) == -1)
            sendError(
                HTTP_BADREQUEST,
                "BAD REQUEST: Content type is multipart/form-data but next chunk does not start with boundary. Usage: GET /example/file.html");
          boundarycount++;
          Properties item = new Properties();
          mpline = in.readLine();
          while (mpline != null && mpline.trim().length() > 0) {
            int p = mpline.indexOf(':');
            if (p != -1)
              item.put(mpline.substring(0, p).trim().toLowerCase(), mpline.substring(p + 1).trim());
            mpline = in.readLine();
          }
          if (mpline != null) {
            String contentDisposition = item.getProperty("content-disposition");
            if (contentDisposition == null) {
              sendError(
                  HTTP_BADREQUEST,
                  "BAD REQUEST: Content type is multipart/form-data but no content-disposition info found. Usage: GET /example/file.html");
            }
            StringTokenizer st = new StringTokenizer(contentDisposition, "; ");
            Properties disposition = new Properties();
            while (st.hasMoreTokens()) {
              String token = st.nextToken();
              int p = token.indexOf('=');
              if (p != -1)
                disposition.put(token.substring(0, p).trim().toLowerCase(), token.substring(p + 1)
                    .trim());
            }
            String pname = disposition.getProperty("name");
            pname = pname.substring(1, pname.length() - 1);

            String value = "";
            if (item.getProperty("content-type") == null) {
              while (mpline != null && mpline.indexOf(boundary) == -1) {
                mpline = in.readLine();
                if (mpline != null) {
                  int d = mpline.indexOf(boundary);
                  if (d == -1)
                    value += mpline;
                  else
                    value += mpline.substring(0, d - 2);
                }
              }
            } else {
              if (boundarycount > bpositions.length)
                sendError(HTTP_INTERNALERROR, "Error processing request");
              int offset = stripMultipartHeaders(fbuf, bpositions[boundarycount - 2]);
              String path = saveTmpFile(fbuf, offset, bpositions[boundarycount - 1] - offset - 4);
              files.put(pname, path);
              value = disposition.getProperty("filename");
              value = value.substring(1, value.length() - 1);
              do {
                mpline = in.readLine();
              } while (mpline != null && mpline.indexOf(boundary) == -1);
            }
            parms.put(pname, value);
          }
        }
      } catch (IOException ioe) {
        sendError(HTTP_INTERNALERROR, "SERVER INTERNAL ERROR: IOException: " + ioe.getMessage());
      }
    }

    /**
     * Find the byte positions where multipart boundaries start.
     **/
    public int[] getBoundaryPositions(byte[] b, byte[] boundary) {
      int matchcount = 0;
      int matchbyte = -1;
      Vector matchbytes = new Vector();
      for (int i = 0; i < b.length; i++) {
        if (b[i] == boundary[matchcount]) {
          if (matchcount == 0) matchbyte = i;
          matchcount++;
          if (matchcount == boundary.length) {
            matchbytes.addElement(new Integer(matchbyte));
            matchcount = 0;
            matchbyte = -1;
          }
        } else {
          i -= matchcount;
          matchcount = 0;
          matchbyte = -1;
        }
      }
      int[] ret = new int[matchbytes.size()];
      for (int i = 0; i < ret.length; i++) {
        ret[i] = ((Integer) matchbytes.elementAt(i)).intValue();
      }
      return ret;
    }

    /**
     * Retrieves the content of a sent file and saves it to a temporary file. The full path to the
     * saved file is returned.
     **/
    private String saveTmpFile(byte[] b, int offset, int len) {
      String path = "";
      if (len > 0) {
        String tmpdir = System.getProperty("java.io.tmpdir");
        try {
          File temp = File.createTempFile("NanoHTTPD", "", new File(tmpdir));
          OutputStream fstream = new FileOutputStream(temp);
          fstream.write(b, offset, len);
          fstream.close();
          path = temp.getAbsolutePath();
        } catch (Exception e) { // Catch exception if any
          myErr.println("Error: " + e.getMessage());
        }
      }
      return path;
    }


    /**
     * It returns the offset separating multipart file headers from the file's data.
     **/
    private int stripMultipartHeaders(byte[] b, int offset) {
      int i = 0;
      for (i = offset; i < b.length; i++) {
        if (b[i] == '\r' && b[++i] == '\n' && b[++i] == '\r' && b[++i] == '\n') break;
      }
      return i + 1;
    }

    /**
     * Decodes the percent encoding scheme. <br/>
     * For example: "an+example%20string" -> "an example string"
     */
    private String decodePercent(String str) throws InterruptedException {
      try {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < str.length(); i++) {
          char c = str.charAt(i);
          switch (c) {
            case '+':
              sb.append(' ');
              break;
            case '%':
              sb.append((char) Integer.parseInt(str.substring(i + 1, i + 3), 16));
              i += 2;
              break;
            default:
              sb.append(c);
              break;
          }
        }
        return sb.toString();
      } catch (Exception e) {
        sendError(HTTP_BADREQUEST, "BAD REQUEST: Bad percent-encoding.");
        return null;
      }
    }

    /**
     * Decodes parameters in percent-encoded URI-format ( e.g.
     * "name=Jack%20Daniels&pass=Single%20Malt" ) and adds them to given Properties. NOTE: this
     * doesn't support multiple identical keys due to the simplicity of Properties -- if you need
     * multiples, you might want to replace the Properties with a Hashtable of Vectors or such.
     */
    private void decodeParms(String parms, Properties p) throws InterruptedException {
      if (parms == null) return;

      StringTokenizer st = new StringTokenizer(parms, "&");
      while (st.hasMoreTokens()) {
        String e = st.nextToken();
        int sep = e.indexOf('=');
        if (sep >= 0)
          p.put(decodePercent(e.substring(0, sep)).trim(), decodePercent(e.substring(sep + 1)));
      }
    }

    /**
     * Returns an error message as a HTTP response and throws InterruptedException to stop further
     * request processing.
     */
    private void sendError(String status, String msg) throws InterruptedException {
      sendResponse(status, MIME_PLAINTEXT, null, new ByteArrayInputStream(msg.getBytes()));
      throw new InterruptedException();
    }

    /**
     * Sends given response to the socket.
     */
    private void sendResponse(String status, String mime, Properties header, InputStream data) {
      try {
        if (status == null) throw new Error("sendResponse(): Status can't be null.");

        OutputStream out = mySocket.getOutputStream();
        PrintWriter pw = new PrintWriter(out);
        pw.print("HTTP/1.0 " + status + " \r\n");

        if (mime != null) pw.print("Content-Type: " + mime + "\r\n");

        if (header == null || header.getProperty("Date") == null)
          pw.print("Date: " + gmtFrmt.format(new Date()) + "\r\n");

        if (header != null) {
          Enumeration e = header.keys();
          while (e.hasMoreElements()) {
            String key = (String) e.nextElement();
            String value = header.getProperty(key);
            pw.print(key + ": " + value + "\r\n");
          }
        }

        pw.print("\r\n");
        pw.flush();

        if (data != null) {
          int pending = data.available(); // This is to support partial sends, see serveFile()
          byte[] buff = new byte[theBufferSize];
          while (pending > 0) {
            int read = data.read(buff, 0, ((pending > theBufferSize) ? theBufferSize : pending));
            if (read <= 0) break;
            out.write(buff, 0, read);
            pending -= read;
          }
        }
        out.flush();
        out.close();
        if (data != null) data.close();
      } catch (IOException ioe) {
        // Couldn't write? No can do.
        try {
          mySocket.close();
        } catch (Throwable t) {}
      }
    }

    private Socket mySocket;
  }

  /**
   * URL-encodes everything between "/"-characters. Encodes spaces as '%20' instead of '+'.
   */
  private String encodeUri(String uri) {
    String newUri = "";
    StringTokenizer st = new StringTokenizer(uri, "/ ", true);
    while (st.hasMoreTokens()) {
      String tok = st.nextToken();
      if (tok.equals("/"))
        newUri += "/";
      else if (tok.equals(" "))
        newUri += "%20";
      else {
        newUri += URLEncoder.encode(tok);
        // For Java 1.4 you'll want to use this instead:
        // try { newUri += URLEncoder.encode( tok, "UTF-8" ); } catch (
        // java.io.UnsupportedEncodingException uee ) {}
      }
    }
    return newUri;
  }

  private int myTcpPort;
  private final ServerSocket myServerSocket;
  private Thread myThread;
  private File myRootDir;

  // ==================================================
  // File server code
  // ==================================================

  /**
   * Serves file from homeDir and its' subdirectories (only). Uses only URI, ignores all headers and
   * HTTP parameters.
   */
  public Response serveFile(String uri, Properties header, File homeDir,
      boolean allowDirectoryListing) {
    Response res = null;

    // Make sure we won't die of an exception later
    if (!homeDir.isDirectory())
      res =
          new Response(HTTP_INTERNALERROR, MIME_PLAINTEXT,
              "INTERNAL ERRROR: serveFile(): given homeDir is not a directory.");

    if (res == null) {
      // Remove URL arguments
      uri = uri.trim().replace(File.separatorChar, '/');
      if (uri.indexOf('?') >= 0) uri = uri.substring(0, uri.indexOf('?'));

      // Prohibit getting out of current directory
      if (uri.startsWith("..") || uri.endsWith("..") || uri.indexOf("../") >= 0)
        res =
            new Response(HTTP_FORBIDDEN, MIME_PLAINTEXT,
                "FORBIDDEN: Won't serve ../ for security reasons.");
    }

    File f = new File(homeDir, uri);
    if (res == null && !f.exists())
      res = new Response(HTTP_NOTFOUND, MIME_PLAINTEXT, "Error 404, file not found.");

    // List the directory, if necessary
    if (res == null && f.isDirectory()) {
      // Browsers get confused without '/' after the
      // directory, send a redirect.
      if (!uri.endsWith("/")) {
        uri += "/";
        res =
            new Response(HTTP_REDIRECT, MIME_HTML, "<html><body>Redirected: <a href=\"" + uri
                + "\">" + uri + "</a></body></html>");
        res.addHeader("Location", uri);
      }

      if (res == null) {
        // First try index.html and index.htm
        if (new File(f, "index.html").exists())
          f = new File(homeDir, uri + "/index.html");
        else if (new File(f, "index.htm").exists())
          f = new File(homeDir, uri + "/index.htm");
        // No index file, list the directory if it is readable
        else if (allowDirectoryListing && f.canRead()) {
          String[] files = f.list();
          String msg = "<html><body><h1>Directory " + uri + "</h1><br/>";

          if (uri.length() > 1) {
            String u = uri.substring(0, uri.length() - 1);
            int slash = u.lastIndexOf('/');
            if (slash >= 0 && slash < u.length())
              msg += "<b><a href=\"" + uri.substring(0, slash + 1) + "\">..</a></b><br/>";
          }

          if (files != null) {
            for (int i = 0; i < files.length; ++i) {
              File curFile = new File(f, files[i]);
              boolean dir = curFile.isDirectory();
              if (dir) {
                msg += "<b>";
                files[i] += "/";
              }

              msg += "<a href=\"" + encodeUri(uri + files[i]) + "\">" + files[i] + "</a>";

              // Show file size
              if (curFile.isFile()) {
                long len = curFile.length();
                msg += " &nbsp;<font size=2>(";
                if (len < 1024)
                  msg += len + " bytes";
                else if (len < 1024 * 1024)
                  msg += len / 1024 + "." + (len % 1024 / 10 % 100) + " KB";
                else
                  msg += len / (1024 * 1024) + "." + len % (1024 * 1024) / 10 % 100 + " MB";

                msg += ")</font>";
              }
              msg += "<br/>";
              if (dir) msg += "</b>";
            }
          }
          msg += "</body></html>";
          res = new Response(HTTP_OK, MIME_HTML, msg);
        } else {
          res = new Response(HTTP_FORBIDDEN, MIME_PLAINTEXT, "FORBIDDEN: No directory listing.");
        }
      }
    }

    try {
      if (res == null) {
        // Get MIME type from file name extension, if possible
        String mime = null;
        int dot = f.getCanonicalPath().lastIndexOf('.');
        if (dot >= 0)
          mime = (String) theMimeTypes.get(f.getCanonicalPath().substring(dot + 1).toLowerCase());
        if (mime == null) mime = MIME_DEFAULT_BINARY;

        // Calculate etag
        String etag =
            Integer.toHexString((f.getAbsolutePath() + f.lastModified() + "" + f.length())
                .hashCode());

        // Support (simple) skipping:
        long startFrom = 0;
        long endAt = -1;
        String range = header.getProperty("range");
        if (range != null) {
          if (range.startsWith("bytes=")) {
            range = range.substring("bytes=".length());
            int minus = range.indexOf('-');
            try {
              if (minus > 0) {
                startFrom = Long.parseLong(range.substring(0, minus));
                endAt = Long.parseLong(range.substring(minus + 1));
              }
            } catch (NumberFormatException nfe) {}
          }
        }

        // Change return code and add Content-Range header when skipping is requested
        long fileLen = f.length();
        if (range != null && startFrom >= 0) {
          if (startFrom >= fileLen) {
            res = new Response(HTTP_RANGE_NOT_SATISFIABLE, MIME_PLAINTEXT, "");
            res.addHeader("Content-Range", "bytes 0-0/" + fileLen);
            res.addHeader("ETag", etag);
          } else {
            if (endAt < 0) endAt = fileLen - 1;
            long newLen = endAt - startFrom + 1;
            if (newLen < 0) newLen = 0;

            final long dataLen = newLen;
            FileInputStream fis = new FileInputStream(f) {
              public int available() throws IOException {
                return (int) dataLen;
              }
            };
            fis.skip(startFrom);

            res = new Response(HTTP_PARTIALCONTENT, mime, fis);
            res.addHeader("Content-Length", "" + dataLen);
            res.addHeader("Content-Range", "bytes " + startFrom + "-" + endAt + "/" + fileLen);
            res.addHeader("ETag", etag);
          }
        } else {
          if (etag.equals(header.getProperty("if-none-match")))
            res = new Response(HTTP_NOTMODIFIED, mime, "");
          else {
            res = new Response(HTTP_OK, mime, new FileInputStream(f));
            res.addHeader("Content-Length", "" + fileLen);
            res.addHeader("ETag", etag);
          }
        }
      }
    } catch (IOException ioe) {
      res = new Response(HTTP_FORBIDDEN, MIME_PLAINTEXT, "FORBIDDEN: Reading file failed.");
    }

    res.addHeader("Accept-Ranges", "bytes"); // Announce that the file server accepts partial
                                             // content requestes
    return res;
  }

  /**
   * Hashtable mapping (String)FILENAME_EXTENSION -> (String)MIME_TYPE
   */
  private static Hashtable theMimeTypes = new Hashtable();
  static {
    StringTokenizer st =
        new StringTokenizer("css		text/css " + "htm		text/html " + "html		text/html "
            + "xml		text/xml " + "txt		text/plain " + "asc		text/plain " + "gif		image/gif "
            + "jpg		image/jpeg " + "jpeg		image/jpeg " + "png		image/png " + "mp3		audio/mpeg "
            + "m3u		audio/mpeg-url " + "mp4		video/mp4 " + "ogv		video/ogg " + "flv		video/x-flv "
            + "mov		video/quicktime " + "swf		application/x-shockwave-flash "
            + "js			application/javascript " + "pdf		application/pdf " + "doc		application/msword "
            + "ogg		application/x-ogg " + "zip		application/octet-stream "
            + "exe		application/octet-stream " + "class		application/octet-stream ");
    while (st.hasMoreTokens())
      theMimeTypes.put(st.nextToken(), st.nextToken());
  }

  private static int theBufferSize = 16 * 1024;

  // Change these if you want to log to somewhere else than stdout
  protected static PrintStream myOut = System.out;
  protected static PrintStream myErr = System.err;

  /**
   * GMT date formatter
   */
  private static java.text.SimpleDateFormat gmtFrmt;
  static {
    gmtFrmt = new java.text.SimpleDateFormat("E, d MMM yyyy HH:mm:ss 'GMT'", Locale.US);
    gmtFrmt.setTimeZone(TimeZone.getTimeZone("GMT"));
  }

  /**
   * The distribution licence
   */
  private static final String LICENCE =
      "Copyright (C) 2001,2005-2011 by Jarno Elonen <elonen@iki.fi>\n"
          + "and Copyright (C) 2010 by Konstantinos Togias <info@ktogias.gr>\n" + "\n"
          + "Redistribution and use in source and binary forms, with or without\n"
          + "modification, are permitted provided that the following conditions\n" + "are met:\n"
          + "\n" + "Redistributions of source code must retain the above copyright notice,\n"
          + "this list of conditions and the following disclaimer. Redistributions in\n"
          + "binary form must reproduce the above copyright notice, this list of\n"
          + "conditions and the following disclaimer in the documentation and/or other\n"
          + "materials provided with the distribution. The name of the author may not\n"
          + "be used to endorse or promote products derived from this software without\n"
          + "specific prior written permission. \n" + " \n"
          + "THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR\n"
          + "IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES\n"
          + "OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.\n"
          + "IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,\n"
          + "INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT\n"
          + "NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\n"
          + "DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\n"
          + "THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n"
          + "(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n"
          + "OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.";
}
